On the identification of the omnivorous humpback fly Megaselia scalaris (Loew)

Ant-decapitating  flies  (lat.  Megaselia scalaris (Loew)) is a quarantine object in the Russian  Federation  and  is  included  in  the Single list of quarantine objects of the Eurasian  Economic  Union,  approved  by  the  of the Council of the Eurasian Economic Commission dated 30.11.2016 No. 158, because it is a vector of dangerous diseases that cause great  economic  damage.  The  range  covers large areas of North America, Africa, southern  Europe,  Australia,  Southeast  Asia,  as well as the European part of Russia, namely the Southern Federal District and the Republic of Crimea. The list of regulated products subject  to  research  to  identify M.  scalaris (Loew) is very extensive, and accurate identification to species of the received samples by entomological method by morphological features of copulatory organs is very labor-intensive and not accurate. Therefore, methods of molecular diagnostics were developed for identification, namely, comparison of the studied  nucleotide  sequence with  the  reference one using NCBI database and determination of genetic distances. The studies were carried out on the basis of the Department of Molecular Research of the North-West Testing Laboratory of FGBU «ARRIAH».  Six samples of the genus Megaselia were used in this work. At the first stage, DNA was isolated  using  DNA-Extran  2  kits.  Then  genetic markers  were  obtained  by  classical  PCR with subsequent detection by electrophoresis using the T100 Thermal Cycler, sequenced on  a  3500  Genetic  Analyzer.  Identification was  performed  by  comparing  the  obtained sequence  in  BioEdit  program  using  NCBI database and by calculating genetic distances using two-parameter Kimura model and Tajima-Nei  model.  The  study  revealed  advantages and disadvantages of the presented methods of molecular identification.

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